1. Field of the Invention
The present invention relates to an image processing technique for converting, for example, a photographic image obtained by photograph taking, into a painting image with an artistic feature such as a water color painting style (snapshot-to-painting conversion).
2. Description of the Related Art
For example, Jpn. Pat. Appln. KOKAI Publication No. 2011-139329 has disclosed an image processing technique for use in converting a photographic image obtained by photograph taking into a painting image (an image that looks like oil painting, water color painting, or the like); the technique uses a facial recognition technique to determine the types (age, gender, race, and the like) of a person present in a photographic image and converts the photographic image into an image of a painting style associated with the determined types of person (subjects the photographic image to a snapshot-to-painting conversion).
However, even with a change of the tone of the image according to the types of the person, this image processing technique relatively beautifully converts scenery, buildings, and the like but fails to naturally convert the details in the image, particularly the portion of the image showing the person. That is, snapshot-to-painting conversion may blur the person's face portion or produce useless brush lines or color tones in the face portion, making the face portion look unnatural. In other words, disadvantageously, the image may be excessively deformed in a painting manner.